NASCAR Cup Series champion Kyle Larson has revealed that he is completely heartbroken by the death of his fellow driver, Kyle Busch.

Tragically, it was confirmed that Busch had died at the age of 41 on Thursday, with the NASCAR community now in mourning as the sport hits Charlotte Motor Speedway.

Larson and Busch never drove for the same team, but the pair have won four Cup Series championships between them, as well as 95 Cup victories.

Such has been their success that there was understandably a mutual respect for each other's talents, and Larson even says that Busch was a big influence on his career.

KYLE BUSCH: Remembering 'Rowdy' after NASCAR legend's tragic death at 41

Kyle Larson reacts to Kyle Busch death

Like many in the NASCAR community, Larson shared a tribute to 'Rowdy' as the tragic news surfaced, writing on his X page: "Completely heartbroken to hear the news of Kyle’s passing.

"I have so many memories of great battles with him throughout my career that I’ll cherish forever. It’s hard to even put into words what he meant to me and my career, whether he knew it or not. He was the bar we all measured ourselves against. Just a pure racer to the core. As real as they come.

"I hate this so much for their family, Samantha, Lennix, and especially Brexton. The bond Kyle and Brexton shared, and everything he poured into his racing and his family, was incredible. RIP KFB."

KYLE BUSCH: NASCAR community pay heartfelt tributes to Kyle Busch after sudden death aged 41